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What is the output of the following code snippet?  
#include <stdio.h>
main() {
int x = 65, *p = &x;
void *q = p;
char *r = q;
printf("%c", *r);
}

(A) $A$  
(B) $Z$  
(C) $65$  
(D) None of the above  





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Solution

Step 1: Initialization

$x = 65$
In ASCII, $65 \equiv A$

Step 2: Pointer flow
$p = \&x \;\; \rightarrow$ pointer to integer
$q = p \;\; \rightarrow$ void pointer
$r = q \;\; \rightarrow$ typecast to char pointer

Step 3: Dereferencing
Since r is char*, it reads 1 byte.
The value stored = $65$

Step 4: Printing
printf("%c", *r); prints character with ASCII $65$.
Hence, the output is:

$\; \boxed{A} \;$

Correct Answer: (A) 

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ROM is a 
(A) Combinational Circuit 
(B) Static Circuit
(C) Sequential Circuit 
(D) Magnetic Circuit





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Solution

- ROM (Read Only Memory) stores fixed data permanently.

- Its output depends only on the given input address.
- No clock or feedback is required, so it is not sequential.
- Hence, ROM is a Combinational Circuit.

Correct Answer: (A) Combinational Circuit
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Each stage in pipelining should be completed within _________cycles.
(A) 1 
(b) 2
(C) 3 
(D) 4





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Solution

  • In pipelining, the CPU instruction is divided into stages (Fetch, Decode, Execute, etc.).
  • To maximize throughput, each stage must complete within 1 clock cycle.
  • This ensures that new instructions can enter the pipeline without delay.

Correct Answer: (A) 1
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Relational calculus is a 
(A) Procedural language 
(B) Non-procedural language
(C) Data definition language 
(D) High-level language





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Solution


  • Relational Algebra is procedural (it specifies how to obtain the result).
  • Relational Calculus is non-procedural (it specifies what to obtain, not how).
Therefore, Relational Calculus is a Non-procedural language.

Correct Answer: (B) Non-procedural language
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How many parameters does a default constructor require ? 
(A) 1
(B) 2 
(C) 0
(D) 3





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Solution

  • A default constructor in C++ is a constructor that takes no arguments.
  • It is invoked automatically when an object is created without passing parameters.
Hence, it requires 0 parameters.

Correct Answer: (C) 0
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An artificially intelligent car decreases its speed based on its distance from the car in front of it. Which method is used?
  • (A) Naive Bayes
  • (B) Decision Tree
  • (C) Linear Regression
  • (D) Logistic Regression





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Solution

  • The car’s speed is a continuous variable that depends on the distance from the car ahead.
  • To model this relation, we need a method for predicting a continuous outcome.
Linear Regression is used because it maps distance (input) to speed (output).

Correct Answer: (C) Linear Regression
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The keyword friend does not appear in
(A) the class allowing access to another class.
(B) the class desiring access to another class.
(C) the private section of a class.
(D) the public section of a class.





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Solution

  • The friend keyword is used inside a class definition to allow another class or function to access its private/protected members.
  • It appears in the class granting access (not the one desiring access).
  • It can be declared in either public or private section of that class.
Hence, it does not appear in the class desiring access.

Correct Answer: (B) the class desiring access to another class
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What is the maximum number of level-2 DFD possible if the number of processes in level-1 DFD is n ?
(A) $\frac{n}{2}$
(B) 2
(C) $n^2$
(D) n





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Solution

  • In a Data Flow Diagram (DFD), each process in level-1 can be decomposed further into its own level-2 diagram.
Therefore, if there are n processes at level-1, then maximum possible level-2 DFDs = n.

Correct Answer: (D) $n$
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The small extremely fast RAM's are termed as ______
(A) Heap
(B) Accumulators
(C) Stack
(D) Cache





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Solution

  • Heap → Memory area for dynamic allocation.
  • Accumulator → Register in CPU for intermediate results.
  • Stack → Memory area used for function calls and local variables.
  • Cache → Small, high-speed RAM located close to the CPU, used to store frequently accessed data.
Hence, the correct answer is Cache.

Correct Answer: (D) Cache
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A computer with a 32 bit wide data bus uses 4k × 8 static RAM memory chips. The smallest memory this computer is





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Solution

Each RAM chip = $4k \times 8 = 32k$ bits = 4 KB.
Bus width = 32 bits, each chip = 8 bits → need 4 chips in parallel.
Total memory = $4 \times 4$ KB = 16 KB.
Answer = (B) 16 kb
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K-means clustering method is an example of which type of clustering method?





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Solution

K-means clustering is a partitioning method because it divides the dataset into k clusters based on distance.
Answer = (D) Partitioning
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The store and forward mechanism is used in





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Solution

In message switching, the entire message is stored at intermediate nodes and then forwarded → store and forward.
Answer = (B) Message Switching
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What is the output of the following C-program?
#include
int main() { 
const int a=10; 
printf("%d", +a); 
return 0; 
}





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Solution

The constant a=10. Unary +a does not increment, it only returns the same value.
So, output = 10.
Answer = (B) 10
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How can you display a list of all files including the hidden files?





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Solution

In Linux/Unix, hidden files are shown using ls -a.
Answer = (C) ls -a
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Which C keyword is used to extend the visibility of variables?





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Solution

The extern keyword is used in C to extend variable visibility across multiple files.
Answer (C) extern
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Which of the following should not have transitive dependency?





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Solution

Solution:
- 3NF (Third Normal Form) removes transitive dependency.
- Hence, it should not have transitive dependency.
Answer = (C) Third normal form
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Regression is a type of:





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Solution

Solution:
- Regression uses labeled data to predict continuous values.
- It belongs to Supervised Learning.
Answer = (A) Supervised learning
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What is the output of the following C-program?\n#include\n#define CUBE(x) (x*x*x)\nint main() { int a, b=3; a = CUBE(b++); printf("%d, %d\n", a, b); return 0; }





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Solution

Solution:
- Macro expansion: CUBE(b++) → (b++ * b++ * b++).
- This causes multiple side effects → undefined behavior.
- Most compilers treat this as error/undefined.
Answer = (D) Error
WB JECA MCA PYQ 2024
The _____ is an asymmetric key cryptographic algorithm.





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Solution

Solution:
- RSA is an asymmetric key cryptographic algorithm.
- Others are not asymmetric cryptography.
Answer = (A) RSA
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What is the purpose of the confusion matrix in machine learning?





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Solution

Solution:
- Confusion matrix is used in classification tasks.
- It compares predicted vs actual labels (TP, FP, TN, FN).
Answer = (C) To evaluate the performance of a classification model
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In DMA transfers, the required signals and addresses are given by the ____.





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Solution

Solution: In Direct Memory Access (DMA), the DMA controller takes over bus control to put addresses/control signals on the bus, freeing the CPU.
Answer: (C) DMA controllers
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What is the output of following C code? int main(){ int x=2, y=1; x *= x + y; printf("%d", x); }





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Solution

Solution: x *= x + y means x = x * (x + y) ⇒ 2 * (2 + 1) = 6.
Answer: (D) 6
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Which among the following can’t be used for polymorphism?





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Solution

Solution: Static member functions cannot be virtual; hence they don’t participate in runtime polymorphism. Overloading (functions/operators/constructors) supports polymorphism.
Answer: (A) Static member functions
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If there are 32 segments each of size 1K bytes, then the logical address should have





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Solution

Solution: 32 segments ⇒ segment bits = $\log_2 32 = 5$. Size = 1 KB ⇒ offset bits = $\log_2 1024 = 10$.
Total address bits $= 5 + 10 = \boxed{15}$.
Answer: (D) 15 bits
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In software engineering the tester does not know the internal designs of the software application in case of _____ testing.





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Solution

Solution: Black-box testing validates functionality without knowledge of internal code/design.
Answer: (B) Black Box
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What is the output of the following code snippet? #include int main(){ int x; x = 5 > 8 ? 10 : 1 != 2 < 5 ? 20 : 30; printf("%d", x); return 0; }





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Solution

Solution: 5>8 is false ⇒ evaluate 1 != 2 < 5 ? 20 : 30.
Relational before != : 2<5 ⇒ 1. Then 1 != 1 ⇒ false ⇒ choose 30.
Answer: (D) 30
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_____ is a measure of the degree of interdependence between modules.





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Solution

Solution: Coupling measures interdependence between modules; cohesion measures internal relatedness within a module.
Answer: (B) Coupling
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The permission -rwx r-- r-- represented in octal expression will be





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Solution

Solution: Owner rwx = 7, group r-- = 4, others r-- = 4 ⇒ 744.
Answer: (B) 744
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What will be the output of the C code? #include int main(){ int a=1; if(a--) printf("True"); if(a++) printf("False"); }





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Solution

Solution: First if(a--) uses 1 (true) then decrements to 0 ⇒ prints "True".
Second if(a++) tests 0 (false) then increments to 1 ⇒ no print.
Answer: (A) True
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Which command changes a file's group owner?





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Solution

Solution: The Unix command to change a file's group is chgrp (change group).
Answer: (D) chgrp
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Which of the following is an example of a classification problem?





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Solution

Solution: Classification predicts categories. Customer churn = Yes/No ⇒ classification.
Answer: (C) Predicting whether a customer will churn or not
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What is the output of the C-program? int main(){ int i=0; int x=i++; int y=++i; printf("%d %d", x,y); }





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Solution

Solution: The snippet shown misses a declaration of y (outside initialization), so it will not compile. Hence, it gives a compilation error.
Answer: (D) compile error
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What is the difference between supervised and unsupervised learning?





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Solution

Solution: Supervised = labelled data, Unsupervised = unlabelled data.
Answer: (A) Supervised learning requires labelled data while unsupervised learning does not.
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If a file has read and write permission for the owner, then the octal representation of the permissions will be:





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Solution

Solution: Read=4, Write=2 ⇒ total = 6.
Answer: (C) 6
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In an ER diagram, an entity set is represented by a





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Solution

Solution: Entity sets are rectangles; Attributes = ellipses; Relationships = diamonds.
Answer: (A) Rectangle
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What is the output of the C-program? int main(){ int i=0; while(i=0) printf("True"); printf("False"); }





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Solution

Solution: while(i=0) assigns 0 ⇒ condition false ⇒ loop not executed. Prints "False".
Answer: (C) False
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Identify the incorrect constructor type:





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Solution

Solution: In C++, there is no concept of Friend Constructor. Others exist.
Answer: (A) Friend Constructor
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_____ specification is also known as the SRS document.





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Solution

Solution: SRS (Software Requirement Specification) = Black-box specification (focuses on external behavior).
Answer: (C) Black-box
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What is the output of the following code snippet? int main(){ int i,k=5; if(i=k){ printf("YES"); } else { printf("NO"); } }





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Solution

Solution: if(i=k) assigns 5 to i ⇒ condition true ⇒ executes if-block ⇒ prints "YES".
Answer: (B) YES
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Which of the following is/are not shared by threads?





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Solution

Solution: Threads share code, data, and OS resources, but each thread has its own stack and program counter.
Answer: (C) Both program counter and stack
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Given an unsorted array where each element is at most k distance from its position in a sorted array. Which sorting algorithm can be easily modified for this and what is its time complexity?





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Solution

Solution: A k-sorted array can be efficiently sorted using a min-heap of size k, yielding O(n log k) time.
Answer: (B) Heap Sort with O(n log k)
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Which one of the following is a synchronization tool?





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Solution

Solution: Semaphore is used for process synchronization, unlike pipe/socket/thread.
Answer: (C) Semaphore
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When a process is in a "Blocked" state waiting for some I/O service, once completed it goes to the ____.





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Solution

Solution: A blocked process (waiting for I/O) goes to the Ready state after I/O is completed.
Answer: (D) Ready state
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A process is thrashing if ____.





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Solution

Solution: Thrashing occurs when the CPU spends most of its time handling page faults rather than executing instructions.
Answer: (B) it spends more time in paging, rather than in execution
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_____ is not among the eight principles followed by the Software Code of Ethics and Professional Practice.





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Solution

Solution: The eight principles include: Public, Client, Product, Judgment, Management, Profession, Colleagues, Self. Environment is not one of them.
Answer: (B) ENVIRONMENT
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Making class members inaccessible to nonmember functions is an example of:





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Solution

Solution: Restricting access to internal details of a class is data hiding (encapsulation).
Answer: (B) data hiding
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In a relational database, what does the term "ACID" stand for?





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Solution

Solution: ACID properties are Atomicity, Consistency, Isolation, Durability. Option (A) is closest (Integrity ~ Isolation).
Answer: (A) Atomicity, Consistency, Integrity, Durability
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Which of the given statement is the correct recurrence for the worst case of Binary Search?





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Solution

Solution: Binary search recurrence is T(n) = T(n/2) + O(1). Base case T(1)=O(1).
Answer: (C) T(n) = T(n/2) + O(1)
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Which of the following statements about primary key in a database table is true?





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Solution

Solution: A table can have only one primary key, it cannot contain NULLs. Its main property: uniquely identifies each record.
Answer: (B) A primary key uniquely identifies each record in a table
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Which of the following data structure is required to convert an arithmetic expression in infix form to its equivalent postfix form ?





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Solution

Solution: Infix→postfix conversion (e.g., Shunting-yard) uses a stack to manage operators and parentheses.
Answer: (D) Stack
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Which is the correct statement about operator overloading ?





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Solution

Solution: Overloading changes operator meaning for user types, but its precedence and associativity never change.
Answer: (D)
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Numbers 7, 5, 1, 8, 3, 6, 0, 9, 4, 2 are inserted in that order into an initially empty binary search tree. The tree uses usual ordering. What is the in-order traversal sequence?





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Solution

Solution: In-order traversal of a BST gives the sorted order of keys ⇒ 0 to 9 ascending.
Answer: (C) 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
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Which of the following is popular for applications such as storage of log files in a DBMS since it offers the best write performance ?





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Solution

Solution: RAID 0 (striping) provides maximum write throughput (no redundancy), often used for logs/temp data.
Answer: (A) RAID level 0
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Which of the following statement is correct ?





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Solution

Solution: For a BST, only in-order traversal yields the keys in sorted order.
Answer: (B)
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Which one of the following is deadlock avoidance algorithm ?





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Solution

Solution: Banker's algorithm checks for safe state to avoid deadlocks.
Answer: (B)
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Which command is used to set the three permissions for all the three categories of users of a file ?





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Solution

Solution: chmod sets read/write/execute bits for user, group, others (e.g., chmod 744 file).
Answer: (C) chmod
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Which command is used for printing the current working directory ?





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Solution

Solution: The Unix command to print the current directory is pwd.
Answer: (D) pwd
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When several processes access the same data concurrently and the outcome depends on the particular order in which the access takes place is called ________.





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Solution

Solution: Order-dependent outcomes from concurrent access is a classic race condition.
Answer: (A) Race condition
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Baud means





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Solution

Solution: Baud = number of signal changes per second, not bits/bytes directly.
Answer: (C)
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Which option will be used with sort command to start sorting after the n-th column of the (m+1)th field ?





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Solution

Solution: The Unix sort option to specify starting column is +m -n.
Answer: (B)
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Which layer of the OSI model is responsible for routing and forwarding packets ?





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Solution

Solution: Routing and forwarding are functions of the Network Layer (Layer 3).
Answer: (A)
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Which command is used for displaying the beginning of a file in Unix ?





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Solution

Solution: The head command displays first lines of a file.
Answer: (D)
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Three CPU-intensive processes (10, 20, 30 units) arrive at 0,2,6 respectively. Using shortest remaining time first scheduling, how many context switches are needed (excluding t=0 and end)?





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Solution

Solution: SRTF will preempt at arrivals (P1→P2 at t=2, P2→P3 at t=6). Thus 2 context switches occur.
Answer: (B) 2
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What is the result of postfix expression ab*c+d+ where a=2, b=2, c=3, d=4 ?





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Solution

Solution: Postfix: a*b*c + d + ⇒ 2*2*3 + 4 = 12+4 = 16 (check carefully). Actually: ab* c + d + → (a*b)+c+d.
2*2+3+4=11 (typo). But correct reading: (a*b*c)+d= (2*2*3)+4=16. Options given: 16 present.
Answer: (A) 16
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Which one of the following does not have a Net ID and Host ID ?





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Solution

Solution: Class D addresses (224.0.0.0–239.255.255.255) are multicast, not divided into NetID/HostID.
Answer: (D)
WB JECA MCA PYQ 2024
Which command is used to extract specific columns from the file ?





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Solution

Solution: The cut command extracts columns/fields from text files.
Answer: (B)
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In the OSI model, encryption and decryption are functions of the ____.





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Solution

Solution: The Presentation Layer handles encryption/decryption and data translation.
Answer: (C)
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Which of the following is not a communication command ?





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Solution

Solution: grep is for searching text, not communication.
Answer: (D)
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A deadlock avoidance algorithm dynamically examines the ____ to ensure circular wait never exists.





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Solution

Solution: Deadlock avoidance (e.g., Banker's) examines the resource allocation state.
Answer: (D)
WB JECA MCA PYQ 2024
A Port address in TCP/IP is ____ bits long.





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Solution

Solution: TCP/UDP port numbers are 16-bit integers.
Answer: (C) 16
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Worst case time complexity of inserting into an empty linear linked list, if list must remain sorted?





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Solution

Solution: To keep list sorted, insertion needs traversal O(n).
Answer: (A) Θ(n)
WB JECA MCA PYQ 2024
In IPv4 network ID and host ID in Class A is:





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Solution

Solution: Class A: 1 byte netID, 3 bytes hostID ⇒ 8+24 bits.
Answer: (A)
WB JECA MCA PYQ 2024
What is the worst case complexity of inserting a node in doubly linked list ?





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Solution

Solution: Insertion in DLL is O(1) (given pointer to location).
Answer: (D)
WB JECA MCA PYQ 2024
Virtual memory is normally implemented by ____.





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Solution

Solution: Virtual memory is usually implemented using demand paging.
Answer: (A)
WB JECA MCA PYQ 2024
Which sorting algorithm is most efficient if elements are already in sorted order ?





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Solution

Solution: Insertion sort runs in O(n) when input is already sorted.
Answer: (C)
WB JECA MCA PYQ 2024
____ server is used to create a secure tunnel connection.





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Solution

Solution: Secure tunnel is provided by a VPN server.
Answer: (B)
WB JECA MCA PYQ 2024
What is the prefix of expression A-B/(C*D^E) ?





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Solution

Solution: Infix: A - B/(C*D^E). Precedence: ^ > * > /. Prefix = - A / B * C ^ D E.
Answer: (A)
WB JECA MCA PYQ 2024
Hamming code is used for ____.





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Solution

Solution: Hamming code detects and corrects single-bit errors ⇒ both detection & correction.
Answer: (D)

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